CN111406417B - Measurement method and apparatus in wireless communication system - Google Patents

Abstract

Embodiments of the present disclosure relate to methods, apparatuses, and computer program products for making measurements in a wireless communication system. A method implemented at a network device comprising: transmitting to the terminal device a configuration of measurement gaps for performing measurements on the terminal device; configuring non-overlapping measurement windows for a plurality of carriers for a terminal device; and instructing the terminal device to measure more than one carrier during one measurement gap occasion. Embodiments of the present disclosure may reduce radio frequency switching time and/or measurement latency.

Description

Measurement method and apparatus in wireless communication system

Technical Field

The non-limiting and example embodiments of the present disclosure relate generally to the field of wireless communications and, in particular, relate to methods, apparatuses, and computer program products for making measurements in a wireless communication system.

Background

In a wireless communication system, it may be necessary for a communication device to perform measurements periodically or based on certain events in order to obtain an estimate of the quality of a radio link between the communication device and another device (e.g., a network device or a terminal device). The estimation of the quality of the radio link may facilitate, for example, mobility management, cell (re) selection, radio link (re) selection and/or carrier (re) configuration of the communication device.

In a wireless communication system operating on multiple carriers, where a base station uses more than one carrier to serve terminal devices within its coverage area, or where neighboring cells operate using different carriers, multi-carrier measurements by the terminal devices may be required. However, how to perform multi-carrier measurements in an efficient manner remains an ongoing problem.

Disclosure of Invention

Various embodiments of the present disclosure are generally directed to methods, apparatuses, and computer program products for improving measurements of communication devices in a wireless communication system. In some embodiments, overhead for measurement is saved. Alternatively or additionally, in some embodiments, the latency for acquiring measurements for multiple carriers is reduced. Other features and advantages of embodiments of the present disclosure will be apparent from the following description of the various embodiments, taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the embodiments of the disclosure.

In a first aspect of the disclosure, a method implemented at a network device is provided. The method comprises the following steps: transmitting to the terminal device a configuration of measurement gaps for performing measurements at the terminal device; configuring non-overlapping measurement windows for a plurality of carriers for a terminal device; and instructing the terminal device to measure more than one carrier during one measurement gap occasion. In one embodiment, configuring non-overlapping measurement windows for multiple carriers may include: non-overlapping measurement windows for multiple carriers are configured within one measurement gap occasion. In another embodiment, each measurement window may be specific to one of the plurality of carriers.

In one embodiment, the information transmitted to the terminal device may indicate at least one of: the number of at least one carrier to be measured during one measurement gap occasion, the index of at least one carrier to be measured during the measurement gap occasion, and the frequency of at least one carrier to be measured during the measurement gap occasion.

In another embodiment, the information may indicate a plurality of carriers to be measured during one measurement gap occasion.

In some embodiments, the configuration of the measurement gap may include at least one of: the length of time of the measurement gap occasion and the repetition period of the measurement gap occasion.

In yet another embodiment, the network device may configure the non-overlapping measurement windows by configuring a time offset for each non-overlapping measurement window.

In a second aspect of the present disclosure, a method implemented at a terminal device is provided. The method comprises the following steps: receiving from the network device a configuration of measurement gaps for performing measurements at the terminal device; receiving a configuration of non-overlapping measurement windows for a plurality of carriers from a network device; determining at least one carrier to be measured during one measurement gap occasion; and performing measurements on at least one carrier based on the received configuration of measurement gaps and the received configuration of non-overlapping measurement windows. In one embodiment, the configuration of the non-overlapping measurement windows for the plurality of carriers may include a configuration of the non-overlapping measurement windows for the plurality of carriers within one measurement gap opportunity. In another embodiment, each measurement window may be specific to one of the plurality of carriers.

In a third aspect of the present disclosure, a network device is provided. The network device comprises processing circuitry and a memory, and said memory contains instructions executable by said processing circuitry, whereby said network device is operable to perform a method according to the first aspect of the present disclosure.

In a fourth aspect of the present disclosure, a terminal device is provided. The terminal device comprises processing circuitry and a memory, and said memory contains instructions executable by said processing circuitry, whereby said terminal device is operable to perform a method according to the second aspect of the present disclosure.

In a fifth aspect of the present disclosure, a computer program is provided. The computer program comprises instructions that, when executed by at least one processing circuitry of a network device, cause the network device to perform a method according to the first aspect of the present disclosure.

In a sixth aspect of the present disclosure, a computer program is provided. The computer program comprises instructions which, when executed by at least one processing circuitry of a terminal device, cause the terminal device to perform a method according to the second aspect of the present disclosure.

In a seventh aspect of the present disclosure, there is provided a computer readable medium having stored thereon a computer program which, when executed by at least one processor of a network device, causes the network device to perform a method according to the first aspect of the present disclosure.

In an eighth aspect of the present disclosure, there is provided a computer readable medium having stored thereon a computer program which, when executed by at least one processor of a terminal device, causes the terminal device to perform a method according to the second aspect of the present disclosure.

Drawings

The above and other aspects, features and advantages of various embodiments of the present disclosure will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings in which like reference characters designate the same or equivalent elements. The accompanying drawings, which are not necessarily drawn to scale, are included to facilitate a better understanding of embodiments of the disclosure, and wherein:

FIG. 1 illustrates an example wireless communication network in which embodiments of the present disclosure may be implemented;

fig. 2 shows an example of synchronization signal and primary broadcast channel block (SSB) composition and mapping for different subcarrier spacings;

FIG. 3 is an example of a measurement gap;

fig. 4 shows a conventional carrier measurement;

fig. 5 illustrates an example of multi-carrier measurement according to an embodiment of the present disclosure;

FIG. 6 illustrates a comparison of switching time overhead between a conventional measurement scheme and a measurement scheme according to an embodiment of the present disclosure;

fig. 7 shows a flow chart of a method in a network device according to an embodiment of the present disclosure;

fig. 8 shows a flowchart of a method in a terminal device according to an embodiment of the present disclosure; and

fig. 9 shows a simplified block diagram of an apparatus that may be embodied as/in a network device and an apparatus that may be embodied as/in a terminal device.

Detailed Description

Hereinafter, the principles and spirit of the present disclosure will be described with reference to illustrative embodiments. It will be understood that all of these embodiments are given solely for the purpose of better understanding and further practicing the invention by those skilled in the art and are not intended to limit the scope of the invention. For example, features illustrated or described as part of one embodiment can be used with another embodiment to yield still a further embodiment. In the interest of clarity, not all features of an actual implementation are described in this specification.

References in the specification to "one embodiment," "an example embodiment," etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Furthermore, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to effect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

It will be understood that, although the terms "first" and "second" may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of example embodiments. As used herein, the term "and/or" includes any and all combinations of one or more of the listed terms.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises," "comprising," "includes," "including," "having," "includes," "including," "containing," "includes" and/or "including" when used herein, specify the presence of stated features, elements, components, and/or groups thereof, but do not preclude the presence or addition of one or more other features, elements, components, and/or groups thereof.

In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

As used herein, the term "wireless communication network" refers to a network that conforms to any suitable wireless communication standard, such as New Radio (NR), long Term Evolution (LTE), LTE-advanced (LTE-a), wideband Code Division Multiple Access (WCDMA), high Speed Packet Access (HSPA), etc. The "wireless communication network" may also be referred to as a "wireless communication system". Furthermore, communication between network devices, between network devices and terminal devices, or between terminal devices in a wireless communication network may be performed according to any suitable communication protocol, including, but not limited to, global system for mobile communications (GSM), universal Mobile Telecommunications System (UMTS), long Term Evolution (LTE), new Radio (NR), wireless Local Area Network (WLAN) standards, such as the IEEE 802.11 standard, and/or any other suitable wireless communication standard currently known or developed in the future.

As used herein, the term "network device" refers to a node in a wireless communication network via which a terminal device accesses the network and receives services from the network. A network device may refer to a Base Station (BS) or an Access Point (AP), e.g., a node B (NodeB or NB), an evolved NodeB (eNodeB or eNB), an NR NB (also known as a gNB), a Remote Radio Unit (RRU), a Radio Header (RH), a Remote Radio Head (RRH), a relay, a low power node (such as a femto, pico, etc.), depending on the terminology and technology applied.

The term "terminal device" refers to any terminal device that may be capable of wireless communication. By way of example, and not limitation, a terminal device may also be referred to as a communication device, user Equipment (UE), subscriber Station (SS), portable subscriber station, mobile Station (MS), or Access Terminal (AT). The terminal devices may include, but are not limited to, mobile phones, cellular phones, smart phones, voice over IP (VoIP) phones, wireless local loop phones, tablets, wearable terminal devices, personal Digital Assistants (PDAs), portable computers, desktop computers, image capture terminal devices (such as digital cameras), gaming terminal devices, music storage and playback appliances, in-vehicle wireless terminal devices, wireless endpoints, mobile stations, notebook computer embedded appliances (LEEs), notebook computer mounted appliances (LMEs), USB dongles, smart devices, wireless Customer Premises Equipment (CPE), and the like. In the following description, the terms "terminal device", "communication device", "terminal", "user equipment" and "UE" may be used interchangeably.

As another example, in an internet of things (IOT) scenario, a terminal device may represent a machine or other device that performs monitoring and/or measurements and transmits the results of such monitoring and/or measurements to another terminal device and/or network device. In this case, the terminal device may be a machine-to-machine (M2M) device, which may be referred to as a Machine Type Communication (MTC) device in a 3GPP context. As one particular example and not limitation, the terminal device may be a UE implementing the 3GPP narrowband internet of things (NB-IoT) standard. Examples of such machines or devices are sensors, metering devices (such as power meters), industrial machinery, or household or personal devices (e.g., refrigerators, televisions, personal wearable devices such as watches, etc.). In other cases, a terminal device may represent a vehicle or other device capable of monitoring and/or reporting its operational status or other functions associated with its operation.

As used herein, downlink (DL) transmission refers to transmission from a network device to a UE, while Uplink (UL) transmission refers to transmission in the opposite direction.

Fig. 1 illustrates an example wireless communication network 100 in which embodiments of the present disclosure may be implemented. As shown, wireless communication network 100 may include one or more network devices, such as network devices 101 and 111. The network device may be of the form: base Stations (BS), node BS (NB), evolved NB (eNB), gNB, virtual BS, base Transceiver Station (BTS) or base station subsystem (BSs), AP, etc.

In this example, network device 101 provides radio connectivity to one set of UEs 102-1, 102-2, and 102-3 (collectively referred to as UE(s) 102 ") that are within its coverage area, while network device 111 provides radio connectivity to another set of UEs 112-1 and 112-2 (collectively referred to as UE(s) 112"). It should be appreciated that in some embodiments, the network device may provide services to fewer or more UEs.

In some embodiments, a network device may use multiple carriers at different frequencies to serve UEs within its coverage area, and each UE may be configured with one or more carriers for its communications. To facilitate mobility management (e.g., handover), cell (re) selection, radio link (re) selection, and/or carrier (re) configuration, the UE may be configured to perform measurements, such as Radio Resource Management (RRM) measurements, for one or more carriers.

In general, due to hardware limitations, a UE may not be able to perform measurements on one carrier while communicating on another carrier. Thus, to avoid unexpected negative effects of the measurement on the ongoing communication, the network device may reserve a time interval for the UE to perform the measurement by configuring a measurement gap for the UE. During the measurement gap, the UE switches its Radio Frequency (RF) chain from the current serving carrier to the carrier to be measured, makes measurements for that carrier, and then switches back to the serving carrier.

As an example, the measurement for the carrier may be performed based on: pilot, reference signals (e.g., but not limited to, cell-specific reference signals (CRS), channel state information reference signals (CSI-RS), and demodulation reference signals (DMRS)), and/or synchronization signals (e.g., primary Synchronization Signals (PSS) and Secondary Synchronization Signals (SSS)).

In the third generation partnership project (3 GPP), the radio access network 1 (RAN 1) working group is discussing measurements based on synchronization signals and a primary broadcast channel block (SSB). Specifically, RAN1 has discussed candidate values for SSB-based RRM measurement timing configuration (SMTC) window durations, and has agreed on SMTC windows of lengths 1ms and 5ms, while other values will be determined later.

In addition, the 3gpp RAN4 working group is discussing requirements for SSB-based measurements, and has agreed to define inter-frequency measurements with RF retuning, i.e. inter-frequency measurements are aided by measurement gaps.

Fig. 2 shows SSB composition and mapping (details can be found in the 3gpp RAN1 chairman statement of the RAN1-nr#2 and RAN1#90 conference) of different subcarrier spacings (SCS) agreed in 3gpp RAN1, where L represents the maximum SSB transmission number in one SS block burst transmission period. As can be seen from fig. 2, the potential SSB transmissions within the 5ms window may be very short, depending on the SCS. For example, for a SCS of 240kHz, the maximum number of SSB transmissions is 64 per cycle, and SSB occurs only in the first 2.25ms of the 5ms window, even though all 64 SSB transmissions are made. Furthermore, in a typical deployment, the network may not transmit all of the maximum number of SSBs, which means that in practice SSBs may occur in even shorter time intervals.

For SSB-based measurements, the measurement gap must overlap with SSB transmissions on the inter-frequency carrier. Since SSB transmission may occur in a short time interval of each transmission period, a long measurement gap cannot be configured in the time domain.

As shown in fig. 3, the actual duration of the measurement gap available to the UE may be referred to as the Measurement Gap Length (MGL), and it consists essentially of measurement time 320 and UE RF switching time 330. The required measurement time 320 is determined by the SMTC window duration, which may vary depending on the number of SSBs transmitted by the network per transmission period. The UE RF switching time 330 is used by the UE to switch its RF chain from the serving carrier to the carrier to be measured and back to the serving carrier after the measurement is performed and is assumed to be 0.25ms to 0.5ms for unidirectional switching depending on the frequency range. Carriers below 6GHz and mmWave may have different RF implementations, resulting in different switching times. Thus, a 6ms MGL is considered as a reference for inter-frequency measurements, including a measurement time of 5ms, 0.5ms for switching the UE RF chain from the serving carrier to the carrier to be measured, and 0.5ms for switching back to the serving carrier.

In evolved universal terrestrial radio access network (E-UTRAN), MGL is defined based on synchronous signal design in Long Term Evolution (LTE) and assumptions of an asynchronous network. With this design, the UE will need the full measurement time per measurement gap per carrier in order to perform measurements on the carriers, including detecting new cells. As a result, conventionally, a fundamental limitation on measurement gaps is that only one carrier is measured in each measurement gap occasion, no matter how long the MGL is. This means that the measurement gap may not be used very efficiently, as the handover overhead is constant, irrespective of the length of the MGL.

In 3gpp RAN4, it has been proposed to shorten the MGL when the SMTC window is small, so as to obtain optimization. For example, 3gpp RAN4 has agreed to support MGL for 3ms, so that in case the necessary measurement time is less than 5ms, for example, when SMTC window duration is only 1ms, time resources can be saved. An example of a measurement scheme with a short MGL is shown in fig. 4. As shown in fig. 4, one layer (i.e., carrier C1, C2, or C3) is measured per measurement gap occasion, and a short MGL 410 is used. However, in this example, the total latency of the measurement is long. For example, if an MGL 410 of 1ms and a Measurement Gap Repetition Period (MGRP) 420 of 20ms are assumed, the UE needs to take 3 gaps to measure all three layers (C1-C3), and the total waiting time is 60ms.

To address at least some of the above issues, methods, apparatus, and computer program products have been presented in this disclosure. In general, according to embodiments of the present disclosure, in order that multi-carrier measurement may be performed within a single measurement gap, so that a small measurement gap is fully utilized, thereby improving the efficiency of use of the measurement gap.

In one embodiment, the network may configure measurement windows (e.g., SMTC windows) over multiple frequency interlayers such that windows on different layers (i.e., carriers) do not overlap each other in the time domain, but are still covered/within measurement gap opportunities, e.g., within an effective measurement time in a 6ms MGL. In one embodiment, the network may configure the UE to measure one or more inter-frequency layers within a single measurement gap. For example, the network device may indicate the number of layers to be measured at each measurement gap occasion and/or indicate one or more particular layers to be measured in the measurement gap occasion. In another example, the UE may decide which layers to measure within each measurement gap.

In some embodiments, during one measurement gap occasion, the UE switches its RF chain from its serving carrier to a different inter-frequency layer indicated by the network, and measures these layers (carriers) one after the other. That is, before the UE switches back to the serving cell, the UE switches its RF chain to layer 1, measures layer 1, switches the RF chain to layer 2, measures layer 1, and so on.

An example of the proposed multicarrier measurement scheme is shown in fig. 5. In this example, three layers 501, 502, and 503 are measured in their corresponding measurement windows, which may be, but are not limited to, SMTC windows, in a single measurement gap occasion with a long MGL 510. That is, only one measurement gap is needed to obtain measurements for all three layers, and if the same 20ms MGRP 520 is assumed, the total latency will be reduced to 20ms.

Additionally, in some embodiments, a reduction in UE RF handover time overhead is achieved. Fig. 6 shows a handover time overhead comparison of the proposed multicarrier measurement scheme and conventional scheme. In a conventional baseline measurement scheme, one layer (carrier) is measured per measurement gap occasion, and in this case four RF handovers are required to measure two layers, namely, handover 601 from serving cell to carrier 1, handover 602 from carrier 1 to serving carrier, handover 603 from serving carrier to carrier 2, and handover 604 from carrier 2 to serving carrier. In contrast, in the proposed scheme, the measurement of two carriers is performed within one measurement gap occasion. Thus, only three RF handovers are measured for both layers, i.e. from serving cell handover 611 to carrier 1, from carrier 1 to carrier 2, and from carrier 2 to 613.

The gain of overhead reduction increases with the number of layers measured in one measurement gap occasion. Thus, greater savings can be realized when measuring more layers in one measurement gap occasion, thereby making the gap-assist measurement more efficient. In NR systems with larger subcarrier spacing, the overhead savings are not trivial, where an overhead savings of 0.5ms represents several additional slots for data communication.

Referring now to fig. 7, fig. 7 shows a flow chart of a method 700 implemented at a network device (e.g., network device 101 or 111 in fig. 1). For ease of discussion, the method 700 will be described below with reference to the network device 101 and the communication network 100 shown in fig. 1. However, embodiments of the present disclosure are not limited thereto.

At block 710, the network device 101 transmits to a terminal device (e.g., one of the UEs 102 in fig. 1) a configuration of measurement gap occasions for performing measurements at the terminal device. For example, and without limitation, the measurements may be performed by the terminal device for one or more of RRM, cell (re) selection, carrier (re) configuration, link (re) selection, etc.

In some embodiments, the configuration of the measurement gap occasion may include a length of time of the measurement gap occasion. For example, the network device 101 may configure a measurement gap of 3ms or 6ms for the terminal device 102. In another embodiment, the configuration of the measurement gap occasions may alternatively or additionally comprise a repetition period of the measurement gap occasions. As an example, the network device 101 may configure a 20ms MGRP for the terminal device 102. It should be understood that any numerical values described herein are for illustration only and are not meant to imply any limitation on the scope of the disclosure.

In contrast to conventional measurement solutions, at block 720, network device 101 configures non-overlapping carrier-specific measurement windows for multiple carriers for terminal device 102. In one embodiment, the configured non-overlapping carrier-specific measurement windows are within a single measurement gap opportunity. That is, multiple measurement windows (e.g., multiple SMTCs) are configured within the same measurement gap opportunity.

Alternatively or additionally, the configured measurement windows do not overlap in time, and each measurement window is carrier-specific (also referred to herein as a layer).

Thus, in some embodiments, the terminal device 102 is enabled to perform measurements on multiple carriers within a single measurement gap occasion. In one embodiment, at block 720, network device 101 may configure a time offset for each of a plurality of non-overlapping measurement windows. The length of each measurement window may be configured, predetermined, or left to the UE implementation.

Although a plurality of measurement windows are configured within one measurement gap occasion, for example, the terminal device 102 may not perform measurement for the corresponding carrier in each configured measurement window. To provide greater flexibility, the particular carrier(s) to be measured may be network device configurable or may be determined by the terminal device. Thus, in one embodiment, at block 730, the network device 101 may instruct the terminal device to measure more than one carrier during one measurement gap occasion. As an example, the network device 101 may transmit information about carriers to be measured during one measurement gap occasion to the terminal device 102. That is, the network device 101 indicates information about one or more carriers to be measured by the terminal device 102 to the terminal device 102.

In one embodiment, at block 730, with the transmitted information, network device 101 may indicate a plurality of carriers to be measured by terminal device 102 during one measurement gap occasion. In another embodiment, the information transmitted at block 730 may indicate the number of carriers (e.g., 2 or 3) to be measured during one measurement gap occasion. In a further embodiment, alternatively or additionally, the transmitted information may indicate an index and/or frequency of at least one carrier to be measured during the measurement gap occasion.

In one embodiment, the carrier on which the terminal device 102 is instructed by the network device 101 to make measurements during one measurement gap occasion at block 730 may comprise the terminal device's current serving carrier. In another embodiment, the carriers to be measured in one measurement gap occasion may include only neighboring cell carriers.

Alternatively or additionally, in a further embodiment, the carriers to be measured in one measurement gap occasion may comprise carriers of a different Radio Access Technology (RAT) than the carriers used by the serving cell of the terminal device. In some embodiments, the carriers to be measured in one measurement gap occasion may include carriers for D2D communications and/or local wireless communications (including WLAN, wiFi, etc.).

The method 700 enables a terminal device to perform multi-carrier measurements during one measurement gap occasion. As discussed with reference to fig. 5 and 6, such an approach may result in a reduction in both handover time overhead and measurement latency.

In addition, in NR systems, the need for measurement gap assisted measurements (including measurements for the serving cell) is greater, and any reduction in overhead can improve system performance. For example, it may enable continuous execution of serving cell measurements.

With the method 700, the network is also enabled to balance measurement latency with available data resources. For example, if latency reduction is the goal, network device 101 may configure terminal device 102 with denser and longer measurement gaps, i.e., more efficient measurement time per layer/carrier configuration, as shown in fig. 5. That is, the method 700 provides flexibility to the network to reduce measurement latency per layer at the expense of more measurement gaps. However, with the conventional measurement method as shown in fig. 4, only one layer/carrier can be measured per measurement gap, and such a choice/tradeoff is not available to the network unless the terminal device 102 is configured with fewer layers/carriers to monitor/measure.

Fig. 8 illustrates a flow chart of an example method 800 implemented at a terminal device (e.g., one of terminal devices 102 and 112). Although for ease of discussion, the method 800 will be described below with reference to the terminal device 102 and the communication network 100 shown in fig. 1, it should be understood that embodiments of the present disclosure are not so limited.

At block 810, the terminal device 102 receives a configuration of measurement gaps from the network device 101 for performing measurements at the terminal device 102. The description provided with reference to method 700 regarding measurements, measurement gaps, measurement gap timings, and configurations thereof also applies herein. For example, in one embodiment, the configuration of the measurement gap received from the network device 101 at block 810 may indicate a length of time of the measurement gap occasion and/or a repetition period of the measurement gap occasion.

At block 820, terminal device 102 receives a configuration of non-overlapping measurement windows for a plurality of carriers from network device 101. In one embodiment, the non-overlapping measurement windows are within one measurement gap opportunity. Alternatively or additionally, each measurement window may be carrier specific. In another example embodiment, the network device 101 may indicate a time offset for each of a plurality of measurement windows. The non-overlapping measurement windows within a single measurement gap occasion enable the terminal device 102 to measure more than one carrier in one measurement gap occasion, thereby reducing the time overhead for RF handover, as shown in fig. 6.

At block 830, the terminal device 102 determines at least one carrier to be measured during one measurement gap occasion. The at least one carrier may be determined based on information received from the network device 101. In one embodiment, at block 830, the terminal device may receive information from the network device 101 regarding at least one carrier to be measured during one measurement gap occasion and determine the at least one carrier based on the received information.

In some embodiments, the terminal device may implicitly determine at least one carrier based on the configuration of the received measurement gap and the configuration of the received non-overlapping measurement window.

At block 840, terminal device 102 performs measurements on at least one carrier according to the received configuration.

In some embodiments, the information received at block 830 is the same as the information transmitted by network device 101 at block 730 using method 700. For example, the information may indicate a plurality of carriers to be measured during one measurement gap occasion. Alternatively or additionally, in one embodiment, the information may indicate one or more of the following: the number of carriers to be measured during one measurement gap occasion, the index of the carriers to be measured during the measurement gap occasion, and the frequency of the carriers to be measured during the measurement gap occasion.

In some embodiments, the terminal device 102 may be configured by the network device 101, or determined by itself, to measure at least one carrier in one measurement gap occasion, and at block 840, the terminal device 102 performs measurements on at least one carrier one after another within one measurement gap occasion, and switches its RF chain to the serving carrier only after all of the at least one carrier is measured, to reduce switching time overhead.

Fig. 9 shows a simplified block diagram of an apparatus 900, which apparatus 900 may be embodied in/as a network device (e.g., network device 101 or 111 shown in fig. 1) or in/as a terminal device (e.g., terminal device 102 or 112 shown in fig. 1).

As shown in the example of fig. 9, the apparatus 900 includes a processor 910 that controls the operation and function of the apparatus 900. For example, in some embodiments, the processor 910 may implement various operations by way of instructions 930 stored in a memory 920 coupled thereto. Memory 920 may be of any suitable type suitable to the local technical environment and may be implemented using any suitable data storage technology, such as semiconductor-based memory terminal devices, magnetic memory terminal devices and systems, optical memory terminal devices and systems, fixed memory, and removable memory, as non-limiting examples. Although only one memory cell is shown in fig. 9, there may be multiple physically distinct memory cells in apparatus 900.

The processor 910 may be of any suitable type suitable to the local technical environment and may include, as non-limiting examples, one or more of the following: general purpose computers, special purpose computers, microprocessors, digital Signal Processors (DSPs), and processors based on a multi-core processor architecture. The apparatus 900 may also include a plurality of processors 910.

Processor 910 can also be coupled to a transceiver 940, with transceiver 940 enabling information to be received and transmitted by way of one or more antennas 950 and/or other components. For example, processor 910 and memory 920 may cooperate to implement method 800 described with reference to fig. 8 or method 700 described with reference to fig. 7. It should be appreciated that all of the features described above with reference to fig. 7-8 are also applicable to the apparatus 900 and therefore will not be described in detail herein.

Various embodiments of the present disclosure may be implemented by a computer program or computer program product, which may be executed by one or more of the following: a processor (e.g., processor 910 in fig. 9), software, firmware, hardware, or a combination thereof.

Although some of the above description is made in the context of the wireless communication system shown in fig. 1, it should not be construed as limiting the spirit and scope of the present disclosure. The principles and concepts of the present disclosure may be more generally applied to other scenarios.

Furthermore, the present disclosure also provides a carrier containing the computer instructions 930. The carrier may be a computer readable storage medium, such as a memory containing a computer program or a computer program product as described above. The computer readable medium may include, for example, magnetic disks, magnetic tape, optical disks, phase change memory, or an electronic memory terminal device such as a Random Access Memory (RAM), read Only Memory (ROM), flash memory device, CD-ROM, DVD, blu-ray disk, etc.

The techniques described herein may be implemented by various means such that an apparatus implementing one or more functions of a corresponding apparatus described using the embodiments includes not only prior art means but also means for implementing one or more functions of a corresponding apparatus described using the embodiments, and may include separate means for each individual function or means that may be configured to perform two or more functions. For example, the techniques may be implemented in hardware (one or more devices), firmware (one or more devices), software (one or more modules), or a combination thereof. For firmware or software, implementations may be made by modules (e.g., procedures, functions, and so on) that perform the functions described herein.

Example embodiments herein have been described above with reference to block diagrams and flowcharts of methods and apparatus. It will be understood that each block of the block diagrams and flowchart illustrations, and combinations of blocks in the block diagrams and flowchart illustrations, respectively, can be implemented by various means including hardware, software, firmware, and combinations thereof. For example, in one embodiment, each block of the block diagrams and flowchart illustrations, and combinations of blocks in the block diagrams and flowchart illustrations, can be implemented by a computer program or computer program product comprising computer program instructions. These computer program instructions may be loaded onto a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions which execute on the computer or other programmable data processing apparatus create means for implementing the functions specified in the flowchart block or blocks.

Moreover, although operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In some cases, multitasking and parallel processing may be advantageous. Also, while the above discussion contains several specific implementation details, these should not be construed as limitations on the scope of the subject matter described herein, but rather as descriptions of features specific to particular embodiments. Certain features that are described in this specification in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a subcombination or variation of a subcombination.

It is obvious to a person skilled in the art that as technology advances, the inventive concept can be implemented in various ways. Those of ordinary skill in the art will appreciate that various modifications and changes can be made without departing from the scope of the present disclosure as set forth in the appended claims. Accordingly, the specification and figures are to be regarded in an illustrative rather than a restrictive sense, and all such modifications are intended to be included within the scope of present disclosure. The protection sought herein is as set forth in the claims below.

Claims (18)

1. A method implemented at a network device, comprising:

transmitting to a terminal device a configuration of measurement gaps for performing measurements at the terminal device;

configuring non-overlapping measurement windows for a plurality of carriers within one measurement gap occasion for the terminal device; and

more than one carrier to be measured during one measurement gap occasion is indicated to the terminal device.

2. The method of claim 1, wherein each of the measurement windows is specific to one of the plurality of carriers.

3. The method of claim 1, wherein the indicating comprises:

transmitting information indicating at least one of:

the number of the at least one carrier to be measured during one measurement gap occasion,

an index of the at least one carrier to be measured during a measurement gap occasion, and

the frequency of the at least one carrier to be measured during the measurement gap occasion.

4. A method according to claim 3, wherein the information indicates a plurality of carriers to be measured during one measurement gap occasion.

5. The method of any of claims 1 to 4, wherein the configuration of the measurement gap comprises at least one of:

measuring the time length of the gap opportunity, and

and repeating the period of the measurement gap opportunity.

6. The method of any of claims 1 to 4, wherein configuring non-overlapping measurement windows comprises:

a time offset is configured for each of the non-overlapping measurement windows.

7. A method implemented at a terminal device, comprising:

receiving from a network device a configuration of measurement gaps for performing measurements at the terminal device;

receiving a configuration of non-overlapping measurement windows for a plurality of carriers within one measurement gap occasion from the network device;

determining at least one carrier to be measured during one measurement gap occasion; and

a measurement is performed on the at least one carrier based on the received configuration of the measurement gap and the received configuration of the non-overlapping measurement window.

8. The method of claim 7, wherein each of the measurement windows is specific to one of the plurality of carriers.

9. The method of claim 7, wherein determining at least one carrier to be measured during one measurement gap occasion comprises:

receiving information from the network device indicating at least one of:

the number of the at least one carrier to be measured during one measurement gap occasion;

an index of the at least one carrier to be measured during a measurement gap occasion; and

the frequency of the at least one carrier to be measured during a measurement gap occasion; and

the at least one carrier is determined based on the received information.

10. The method of claim 9, wherein the information indicates a plurality of carriers to be measured during one measurement gap occasion.

11. The method of claim 7, wherein determining at least one carrier to be measured during one measurement gap occasion comprises:

the at least one carrier is determined based on the received configuration of the measurement gap and the received configuration of the non-overlapping measurement window.

12. The method of claim 7, wherein performing measurements on the at least one carrier comprises:

performing measurements on the at least one carrier one by one within the one measurement gap occasion; and

the radio frequency, RF, chain of the terminal device is switched to the serving carrier of the terminal device only after all of the at least one carrier have been measured.

13. The method of any of claims 7 to 12, wherein the configuration of the measurement gap indicates at least one of:

measuring the time length of the gap opportunity; and

and repeating the period of the measurement gap opportunity.

14. The method according to any of claims 7 to 12, wherein the configuration of non-overlapping measurement windows comprises:

time offset for each of the non-overlapping measurement windows.

15. A network device comprising processing circuitry and memory containing instructions executable by the processing circuitry, whereby the network device is operable to perform the method of any one of claims 1 to 6.

16. A terminal device comprising processing circuitry and memory containing instructions executable by the processing circuitry, whereby the terminal device is operable to perform the method of any of claims 7 to 14.

17. A computer readable medium having stored thereon a computer program which, when executed by at least one processor of a network device, causes the network device to perform the method according to any of claims 1 to 6.

18. A computer readable medium having stored thereon a computer program which, when executed by at least one processor of a terminal device, causes the terminal device to perform the method according to any of claims 7 to 14.